Blend the soaked and strained almonds, water, and sweetener in a blender until smooth. Strain the mixture with cheesecloth on top of a bowl, so that you get a nice white almond milk. You can use the leftover almond pulp for example in crackers or bread rolls. If you want your yogurt to be thicker, add agar agar and boil the almond milk in a pot carefully for about 5 – 7 minutes. Take the pot from the stove and let it cool down (to a body temperature). Pour in the probiotics and mix. Pour the yogurt into a sealable clean (boiled or washed in a dish machine) dry glass jar. Close the jar with a lid or cover with a cheesecloth and a rubber band. Turn the oven light on but do not heat the oven. The oven light should keep the oven warm enough for the yogurt. Place the yogurt in the oven with the light on and leave the yogurt to set for about 8 – 12 hours. The longer you let the yogurt ferment, the stronger and sourer the flavor will be. Store the yogurt in an airtight container/jar in the refrigerator.